MINIATURE GPS DATA LOGGERS REVEAL HABITAT AFFILIATIONS AND MOVEMENT OF VEERY (CATHARUS FUSCESCENS) DURING THEIR FIRST NON-TRANSIENT PERIOD IN SOUTH AMERICA

Abstract

The ecology of Nearctic-Neotropical migrant songbirds in South America is largely unexplored. We used miniature global positioning system (GPS) data loggers to determine the broad habitat associations of nine Veeries (Catharus fuscescens) during their first non-transient period in South America. Because Veeries undertake an intratropical migration between two separate non-transient periods, the habitat used by settled birds in South America cannot not be determined from field observation or the capture of single unmarked individuals. Using satellite images, we examined coarse habitat characteristics at GPS positions from the tagged birds during their first non-transient period (December – February). We also examined habitat descriptions from existing records (e.g., published literature, museum records) of multiple birds from single sites that we consider settled individuals. All records we accepted as birds settled during their first non-transient period, including birds we tagged, were associated with stunted forest on nutrient poor soils primarily on elevated cerrado and white sand enclaves (~200 – 750 m) on the Brazilian Shield in southern Amazonia (cerrado, cerradão, savana metalófita – canga, campinarana, sartenejal). Notably, these uncommon forest communities are geographically limited and severely threatened due to anthropogenic conversion. Therefore, because of restricted habitat availability and the species’ recent population decline, we believe the Veery’s current global conservation status should be reconsidered. Following Nearctic-Neotropical migration, tagged individuals exhibited three behaviors prior to intratropical migration: (1) a prolonged stationary period at a single site, (2) shorter stationary periods with relocation events, (3) apparent continual movement. Our results have significant importance in terms of understanding the ecology and conservation needs of this declining species and demonstrate the utility of GPS loggers in tracking songbirds through dense tropical vegetation in remote and inaccessible regions of South America.